Precise and Portable Antenna Test System (PAPATS)

The Naval Surface Warfare Center, Crane Divison (NSWC Crane) has developed, built, and patented the precise and portable antenna test system (PAPATS), which can be set up in the actual field environments where an antenna system would be deployed. PAPATS employs near-field techniques in a manner that can quickly and accurately measure far-field signal patterns. The device consists of a computer, a robotic positioner, a probe, and the antenna under test (AUT). The robot can move the probe, the AUT, or both over the desired test surface. Additionally, either the probe or the AUT can transmit while the other receives.

Traditional near-field testing occurs either in fixed indoor facilities or on a large diameter turntable. Indoor facilities are not able to replicate the diverse impacts caused by differing ground surfaces, such as asphalt, grass, and sand. Turntables can also introduce errors into the testing process. Far-field testing requires large areas which are increasingly difficult to secure, and the vast distances increase the likelihood of interference from terrain, vegetation, weather, buildings, and other signals. PAPATS employs a highly precise real-time kinematic global positioning system (RTK GPS), coupled with an inertial measurement unit (IMU) to provide the precision of an indoor facility in a field portable system.

Advantages:-Precise: Indoor positional accuracy in a portable outdoor unit. IMU provides pointing accuracy within 1/2 degree and RTK GPS provides location accuracy of 1 cm horizontally and 2 cm vertically-Portable: Can be set up outdoors in a variety of field environments in order to assess the impacts of varied ground materials on antenna patterns-Efficient: Thoroughly determine far-field antenna patterns and polarization measurements for high frequency antennas in a small test range space